So Pearl and Marina's canon heights are given in The Art of Splatoon 2. Pearl is 145 cm (~4 feet 9 inches) tall, Marina is 180 cm (~5 feet 10 inches) tall.
The models are accurate to that scale. So theoretically, we can use this scale to get the canon heights of the other idols.
Therefore going off this scale: Callie and Marie are both 5'2", Shiver is about 5'4", Frye's 5'5", and Big Man is almost 7'3".